In the present work, we report on a 2.5-year-old male patient with typical clinical features of partial trisomy of the distal third of chromosome 10 long arm. The karyotype was: 46,XY, dir dup(10)(q25.2-25.3-->qter). The identification of the duplicated segment was carried out by the fluorescence in situ hybridization technique using region-specific probes. The proband's phenotype is compared with previously reported cases.